Radio-frequency identification (RFID) is the wireless use of radio-frequency electromagnetic fields to transfer data, often used to automatically identify and/or track objects via RFID devices attached to or otherwise associated with the objects. The RFID devices may contain electronically stored information. Some devices are powered by and read at short ranges (a few centimeters to a few meters) via magnetic fields (electromagnetic induction). These devices typically have no battery. Rather, they collect energy from the interrogating electromagnetic field. Other devices may use one or more local power sources such as a battery and then act as a transponder to emit radio waves. Battery powered tags may operate at up to hundreds of meters. RFID tags may be included in seals as described in U.S. Pat. No. 8,282,013, incorporated by reference herein in its entirety.